CA2685105C - Improved compressed air foam technology - Google Patents
Improved compressed air foam technology Download PDFInfo
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- CA2685105C CA2685105C CA2685105A CA2685105A CA2685105C CA 2685105 C CA2685105 C CA 2685105C CA 2685105 A CA2685105 A CA 2685105A CA 2685105 A CA2685105 A CA 2685105A CA 2685105 C CA2685105 C CA 2685105C
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- foam
- pressure
- foaming chamber
- flow rate
- volume flow
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- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62C—FIRE-FIGHTING
- A62C5/00—Making of fire-extinguishing materials immediately before use
- A62C5/02—Making of fire-extinguishing materials immediately before use of foam
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- Health & Medical Sciences (AREA)
- Public Health (AREA)
- Business, Economics & Management (AREA)
- Emergency Management (AREA)
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- Accessories For Mixers (AREA)
- Cleaning By Liquid Or Steam (AREA)
- Fire-Extinguishing Compositions (AREA)
Abstract
The method is for continuously producing compressed-air foam, notably for fire fighting or for decontamining, by supplying both compressed air and a mixture of water and at least a foaming agent to a foaming chamber (5) outputting foam to a nozzle (9) via a pipe (8). The mixture of foam agent and water and the compressed air are each continuously supplied to the foaming chamber (5) at a constant pressure and at a constant volume flow rate, e.g. by means of pressure regulators (1, 2) and of flow rate regulators (3, 4). The foam pressure is regulated at the outlet of the foaming chamber (5) for maintaining the foam mixing pressure in the foaming chamber constant, preferably by a self-operating valve (6). The foaming chamber can advantageously be of a static type comprising sieves.
Description
, CA 02685105 2014-08-06 , IMPROVED COMPRESSED AIR FOAM TECHNOLOGY
FIELD OF THE INVENTION
The invention relates to a method for continuously producing compressed-gas foam, in particular compressed-air foam and a compressed gas foam system, in particular a compressed-air foam system, notably for extinguishing fire as well as a foaming chamber particularly adapted therefore.
BACKGROUND OF THE INVENTION
It is known in the art to fight fire with compressed-air foam (CAF).
Typically, a foaming agent is added continuously to a water flow and the resulting flow of the mixture of foam agent and water is supplied to a foaming line or chamber which is also supplied with air pressure so as to generate foam. The foam exiting the foaming line or chamber passes through a rigid or flexible pipe to a nozzle for ejecting the foam onto the fire. The foaming line or chamber, also designated as a mixer or a mixing chamber, is usually of a static type, alternatively called motionless, i.e. without moving parts.
Compressed air foam systems (CAFS) may be mobile e.g. when mounted on a fire-emergency vehicle. They may also be fixed e.g. when used in fixed fire-security systems in tunnels for car and truck traffic.
Various technologies for producing CAF exist which are often very different from each others.
A major problem for producing CAF is to control in an appropriate way the water flow and the air flow supplied to the mixing chamber so as to provide continuously foam having adequate properties for fighting fire and that remain stable over time. The problem arises due to the fact that both the water and air supplied to the mixing chamber and the physical conditions in the pipes and nozzles for transporting and ejecting foam may vary. In particular, the CAFS may be supplied with a water flow the pressure and flow rate of which may vary over time e.g. when using water pumps. Mobile systems may be used with water sources such as hydrants available at the spot of intervention and that can thus have different
FIELD OF THE INVENTION
The invention relates to a method for continuously producing compressed-gas foam, in particular compressed-air foam and a compressed gas foam system, in particular a compressed-air foam system, notably for extinguishing fire as well as a foaming chamber particularly adapted therefore.
BACKGROUND OF THE INVENTION
It is known in the art to fight fire with compressed-air foam (CAF).
Typically, a foaming agent is added continuously to a water flow and the resulting flow of the mixture of foam agent and water is supplied to a foaming line or chamber which is also supplied with air pressure so as to generate foam. The foam exiting the foaming line or chamber passes through a rigid or flexible pipe to a nozzle for ejecting the foam onto the fire. The foaming line or chamber, also designated as a mixer or a mixing chamber, is usually of a static type, alternatively called motionless, i.e. without moving parts.
Compressed air foam systems (CAFS) may be mobile e.g. when mounted on a fire-emergency vehicle. They may also be fixed e.g. when used in fixed fire-security systems in tunnels for car and truck traffic.
Various technologies for producing CAF exist which are often very different from each others.
A major problem for producing CAF is to control in an appropriate way the water flow and the air flow supplied to the mixing chamber so as to provide continuously foam having adequate properties for fighting fire and that remain stable over time. The problem arises due to the fact that both the water and air supplied to the mixing chamber and the physical conditions in the pipes and nozzles for transporting and ejecting foam may vary. In particular, the CAFS may be supplied with a water flow the pressure and flow rate of which may vary over time e.g. when using water pumps. Mobile systems may be used with water sources such as hydrants available at the spot of intervention and that can thus have different
2 pressure and flow rate characteristics. Further, the length and diameter of the pipes connected to the outlet of the mixing chamber, the type of nozzle connected at the end of the pipe, the extent of elevation of the pipe, the number of the pipes connected to the outlet of the mixing chambers, among others, may vary and influence the working conditions of the mixing chamber and thereby the foam quality.
Therefore, complex systems and processes are used for balancing the pressure of water and the pressure of air supplied to the mixing chamber or for adapting the pressure of air when the pressure of water varies.
US-A-2004/0177975 discloses a CAFS comprising a system controller for controlling an air flow control valve depending on the signals provided by a water flowmeter and an air flowmeter with a view of maintaining a ratio of air flow to foam flow based upon the user adjustable ratio input.
WO 2006/000177 discloses a CAFS in which compressed air is conducted into a foaming line via an air pressure controller and an air volume flow rate control valve. Further, produced CAF flows via a foam pressure sensor and an electro-pneumatically operated valve, that form a closed-loop control circuit for setting the foam consistency and consequently the foam quality, to the foam ejection device. Water is fed into the system via a water pressure controller and is intermixed with a foaming agent and an additive. The foaming agent-additive-water mixture flows via a water volume flow rate control valve and the foaming line into which compressed air is inserted at preset pressure and volume flow rate parameters via the air volume flow rate control valve. This document mentions that the foam quality of the CAF spread using a foam ejecting device depends on the flow rate and therefore on the dwell time of the foam in the foaming line and teaches to control it via the foam pressure determined by a foam pressure sensor using the electro-pneumatically operated valve (foam pressure control).
However, this document does not give any detail on the way of controlling the different parameters, in particular pressure, volume flow rate and speeds/dwell time of air, water and foam so as to ensure that the mixing chamber provides continuously foam of good
Therefore, complex systems and processes are used for balancing the pressure of water and the pressure of air supplied to the mixing chamber or for adapting the pressure of air when the pressure of water varies.
US-A-2004/0177975 discloses a CAFS comprising a system controller for controlling an air flow control valve depending on the signals provided by a water flowmeter and an air flowmeter with a view of maintaining a ratio of air flow to foam flow based upon the user adjustable ratio input.
WO 2006/000177 discloses a CAFS in which compressed air is conducted into a foaming line via an air pressure controller and an air volume flow rate control valve. Further, produced CAF flows via a foam pressure sensor and an electro-pneumatically operated valve, that form a closed-loop control circuit for setting the foam consistency and consequently the foam quality, to the foam ejection device. Water is fed into the system via a water pressure controller and is intermixed with a foaming agent and an additive. The foaming agent-additive-water mixture flows via a water volume flow rate control valve and the foaming line into which compressed air is inserted at preset pressure and volume flow rate parameters via the air volume flow rate control valve. This document mentions that the foam quality of the CAF spread using a foam ejecting device depends on the flow rate and therefore on the dwell time of the foam in the foaming line and teaches to control it via the foam pressure determined by a foam pressure sensor using the electro-pneumatically operated valve (foam pressure control).
However, this document does not give any detail on the way of controlling the different parameters, in particular pressure, volume flow rate and speeds/dwell time of air, water and foam so as to ensure that the mixing chamber provides continuously foam of good
3 quality for extinguishing fire. Further, the closed-loop control may be complicated to implement.
EP-A-1 632 272 discloses a CAFS for a tunnel for car and truck traffic. This document does not deal with the problem of optimizing the working conditions of the mixing chamber, but with the problem of allowing ejection of foam having a good quality despite the fact that foam is transported over long pipes. Therefore, this document teaches to set automatically the foam pressure to a given pressure behind the mixing chamber in view of preventing the foam pressure to get below a determined value at the foam-ejection device and providing thereby consistent foam still having high extinguishing property. The foam pressure behind the mixing chamber is obtained with an adjustable cross section restriction of the pipe by means of a valve controlled with respect to a pressure sensor.
However, this document does not deal at all with the problem of controlling the different parameters, in particular pressure, volume flow rate and speeds/dwell time of air, water and foam so as to ensure that the mixing chamber provides continuously foam of good quality for extinguishing fire.
SUMMARY OF THE INVENTION
The problem of the invention is to provide an improved technology for continuously producing CAF, or more generally compressed-gas foam, with a high and constant quality and which is simple to implement, notably for the purpose of extinguishing fire or decontamination of objects.
This object is achieved with a method for continuously producing compressed-gas foam, in particular compressed-air foam, notably for fire fighting or for decontamining, by supplying both compressed gas, preferably air, and a mixture of liquid, preferably water, and at least a foam agent to a foaming chamber having an outlet for outputting foam, comprising the steps of:
- continuously supplying the mixture of foam agent and liquid to the foaming chamber at a first constant pressure and at a first constant volume flow rate;
. CA 02685105 2014-08-06
EP-A-1 632 272 discloses a CAFS for a tunnel for car and truck traffic. This document does not deal with the problem of optimizing the working conditions of the mixing chamber, but with the problem of allowing ejection of foam having a good quality despite the fact that foam is transported over long pipes. Therefore, this document teaches to set automatically the foam pressure to a given pressure behind the mixing chamber in view of preventing the foam pressure to get below a determined value at the foam-ejection device and providing thereby consistent foam still having high extinguishing property. The foam pressure behind the mixing chamber is obtained with an adjustable cross section restriction of the pipe by means of a valve controlled with respect to a pressure sensor.
However, this document does not deal at all with the problem of controlling the different parameters, in particular pressure, volume flow rate and speeds/dwell time of air, water and foam so as to ensure that the mixing chamber provides continuously foam of good quality for extinguishing fire.
SUMMARY OF THE INVENTION
The problem of the invention is to provide an improved technology for continuously producing CAF, or more generally compressed-gas foam, with a high and constant quality and which is simple to implement, notably for the purpose of extinguishing fire or decontamination of objects.
This object is achieved with a method for continuously producing compressed-gas foam, in particular compressed-air foam, notably for fire fighting or for decontamining, by supplying both compressed gas, preferably air, and a mixture of liquid, preferably water, and at least a foam agent to a foaming chamber having an outlet for outputting foam, comprising the steps of:
- continuously supplying the mixture of foam agent and liquid to the foaming chamber at a first constant pressure and at a first constant volume flow rate;
. CA 02685105 2014-08-06
4 - continuously supplying the compressed gas to the foaming chamber at a second constant pressure and at a second constant volume flow rate; and - regulating the foam pressure at the outlet of the foaming chamber for maintaining the foam mixing pressure in the foaming chamber constant by using a self-operating valve connected to the outlet of the foaming chamber.
Preferred embodiments of the method comprise one or more of the following features:
- regulating the foam pressure at the outlet of the foaming chamber for maintaining the foam mixing pressure in the foaming chamber at a determined value;
- providing the possibility to selectively adjust said determined value;
- the self-operating valve is preferably a pinch valve connected to the outlet of the foaming chamber for the step of regulating the foam pressure;
- the self-operating valve is adapted to regulate the foam pressure at the outlet of the foaming chamber with respect to a target air pressure applied to the self-operating valve;
- using a pressure regulator and a volume flow rate regulator for continuously supplying the mixture of foam agent and liquid to the foaming chamber at a first constant pressure and at a first constant volume flow rate;
- using a pressure regulator and a volume flow rate regulator for continuously supplying the compressed gas to the foaming chamber at a second constant pressure and at a second constant volume flow rate;
- setting the first volume flow rate for causing the superficial velocity of the mixture of foam agent and liquid in the foaming chamber to be at least 0.3 m/s, and more preferably at least 2 m/s;
- setting the first volume flow rate for causing the flow speed of the mixture of foam agent and liquid in the mixing chamber to be not more than 3 m/s;
- setting the second volume flow rate for causing the superficial velocity of the compressed-gas in the mixing chamber to be at least 0.3 m/s, and more preferably at least 2 m/s;
- setting the second volume flow rate for causing the superficial velocity of the compressed-gas in the mixing chamber to be not more than 3 m/s;
- setting the first and the second volume flow rates for providing in the mixing chamber a relative gas speed ratio greater than 0.3, more preferably greater than or equal to 0.4, and still more preferably greater than or equal to 0.5, but not more than 0.95, more preferably not more than 0.8 and more advantageously not more than 0.75;
- connecting one end of a pipe to the outlet of the foaming chamber, the other end of the pipe being connected to a foam-ejecting device, wherein the hydraulic cross section of the pipe is at least equal or greater than the hydraulic cross section of the foaming chamber.
According to another aspect, the invention proposes a compressed gas foam system, in particular a compressed air foam system, comprising:
- a foaming chamber having:
= a first inlet port for supplying compressed gas, preferably air, to the foaming chamber, = a second inlet port for supplying a mixture of liquid, preferably water, and at least one foam agent to the foaming chamber, and = an outlet port for outputting foam; and - a pressure-regulating arrangement connected to the outlet port for maintaining constant the foam pressure at the outlet of the foaming chamber characterized in that the pressure-regulating arrangement comprises a self-operating valve.
Preferred embodiments of the system comprise one or more of the following features:
- a pressure regulator for continuously supplying the mixture of foam agent and liquid to the foaming chamber at a first constant pressure;
- a volume flow rate regulator for continuously supplying the mixture of foam agent and liquid to the foaming chamber at a first constant volume flow rate;
- a pressure regulator for continuously supplying the compressed gas to the foaming chamber at a second constant pressure;
- a volume flow rate regulator for continuously supplying the compressed gas to the foaming chamber a second constant volume flow rate;
. CA 02685105 2014-08-06 - the self-operated valve, preferably comprises a pinch valve;
- a pipe connected to the outlet of the foaming chamber, the other end of the pipe being connected to a foam-ejecting device, wherein the hydraulic cross section of the pipe is at least equal or greater than the hydraulic cross section of the foaming chamber;
- the system is designed to implement the method according to the invention.
Within the invention as previously defined, the mentioned compressed gas can consist in a single gas, but can also be a mixture of several different gases as is the case for air. Similarly, within the invention, the mentioned liquid can consist in a single liquid, but can also be a mixture of several different liquids.
Further features and advantages of the invention will appear from the following description of embodiments of the invention, given as non-limiting examples, with reference to the accompanying drawings listed hereunder.
BRIEF DESCRIPTION OF THE DRAWING
Fig. 1 shows schematically a CAFS according to an embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
According to the invention, CAF is continuously produced by supplying both water containing at least a foaming agent and compressed air to a foaming chamber having an outlet for outputting. The mixture of foam agent and water is continuously supplied to the foaming chamber at a first constant pressure and at a first constant volume flow rate.
Similarly, the compressed air is continuously supplied to the foaming chamber at a second constant pressure and at a second constant volume flow rate. Further, the pressure in the foaming chamber ¨ that we will call hereafter foam mixing pressure - is regulated for maintaining said foam pressure constant, regardless of the possible lower pressure in the foam transporting line(s) connected at the outlet of the foaming chamber. The mentioned continuous production of foam and the continuous supply of compressed air and of the mixture of foam agent and water relates to the case in which the CAFS in use, i.e. in particular when the foam-ejecting device such as a nozzle arranged at the end of a pipe . CA 02685105 2014-08-06 connected to the outlet of the foaming chamber, is open. One will understand that the mentioned pressure regulation for maintaining the foam mixing pressure constant in the foaming chamber does not necessarily involve that the pressure is the same at any location through the foaming chamber. Indeed, the different parts of the foaming chamber may cause some pressure loss and as a result the pressure may differ somewhat from one location to another in the foaming chamber. It should be understood instead that as a consequence of the mentioned pressure regulation, the pressure does not substantially vary over time when considering a given location in the foaming chamber.
As a consequence, compressed air and the mixture of foam agent and water flow through the mixing chamber with each having a constant volume flow rate and a constant flow speed, independently notably of subsequent variation of pressure that may occur in the pipe(s) for transporting the foam from the foaming chamber to foam-ejecting devices. As a result, foam is continuously output by the foaming chamber with a constant quality. Further, there is no need for balancing the pressure and the volume flow rate of the compressed air and the mixture of foam agent and water.
Fig. 1 shows a CAFS according to a preferred embodiment of the invention. The CAFS
comprises a foaming chamber 5 supplied continuously with a mixture of water and at least one foam agent via a pressure regulator 2 and a volume flow rate regulator 4.
The foaming agent may be of any type suitable for fire fighting. Foaming chamber 5 is also supplied continuously with compressed air via a pressure regulator 1 and a volume flow rate regulator 3. Pressure regulators 1, 2 and volume flow rate regulators 3, 4 are provided with a view of supplying foaming chamber 5 with constant pressure and volume flow rates of air and of the mixture of foam agent and water, despite possible changes in the air source and/or in the water source. Foaming chamber 5 mixes the inputted compressed air and the mixture of foam agent and water to produce foam. Foaming chamber 5 may be of any known type.
Preferably, foaming chamber 5 is a static mixing chamber.
Water may be supplied from any suitable water source (not represented) such as a fire pump, a hydrant or a fixed water supply network in a building or a tunnel. Compressed air may classically be supplied by a compressor. Foaming agent is added continuously and homogeneously to water in an appropriate quantity by any appropriate technique such as described for instance in WO 2006/000177. The quantity of foaming agent added to the water is usually less than 1% of the total volume of the mixture of water and foam agent.
The outlet of foaming chamber 5 is connected to a pipe 8 for transporting the foam. A
foam-ejecting device 9 such as a nozzle is connected at the end of pipe 8.
Pipe 8 may be rigid or flexible according to the intended use. A pressure-regulating arrangement 6, 7 is arranged in pipe 8 at the outlet of foaming chamber 5. Pressure-regulating arrangement 6, 7 is adapted to maintain a constant pressure at the outlet of foaming chamber 5 and as a result it maintains also the foam mixing pressure in foaming chamber 5 constant. Thus, the foam mixing pressure in foaming chamber 5 does not vary due to the subsequent condition of pipe 8 and foam-ejecting device 9.
The foam pressure in foaming chamber 5 is maintained at a pressure that is set lower to the pressure of the mixture of foam agent and water and of the compressed air at the outlets of pressure regulators 1 and 2.
Maintaining the foam mixing pressure constant in foaming chamber 5 makes it possible to produce continuously foam with precisely controlled working parameters in the foaming chamber and that are stable over time. As a result, foam can be continuously produced with a constant quality. It has been found that this result is achieved due to the fact that the volume flow rates of air and of the mixture of foam agent and water that are determined by volume flow rate regulators 3, 4 set to given values are actually influenced by the difference of pressure between the inlet and the outlet of the volume flow rate regulators 3, 4. The fact of maintaining the foam mixing pressure constant in foaming chamber 5 in combination with pressure regulators 1, 2 causes the differences of pressure at the volume flow rate regulators 3, 4 to remain constant. As a consequence, the actual flow rates of air and of the mixture of foam agent and water supplied to foaming chamber 5 are constant too.
Pressure regulators 1, 2 may be pressure-limiting valves, notably of the type available on the market. Volume flow rate regulators 3, 4 may be volume flow rate regulating valves, notably of the type available on the market.
Further, pressure-regulating arrangement 6, 7 preferably comprises a self-operating valve 6, notably such as available on the market. In this case, the degree of aperture of the flow path through valve 6 is determined by the back pressure of the foam in pipe 8 and foam-ejecting device 9 in conjunction with the target pressure of valve 6.
As a result, there is no need of pressure sensors and controlling means such as a PLC
or an electronic circuit with a microcontroller for achieving a constant foam pressure. In other words, a self-operating valve provides for a very simple and cheap implementation.
Self-operating valve 6 is preferably adjustable. In other words, it is possible to selectively set self-operating valve 6 to a certain target pressure according to the wished water-air ratio. And as a consequence, self-operating valve 6 regulates the foam mixing pressure in foaming chamber 5 so as to equal the target pressure. As a consequence, it is possible to change the foam mixing pressure in foaming chamber 5 and thereby adjust the flow speed.
In a preferred embodiment shown in Fig. 1, the target pressure is provided pneumatically to self-operating valve 6. The target pressure may be provided via a pressure control valve 7 connected to the compressed air source used for supplying foaming chamber
Preferred embodiments of the method comprise one or more of the following features:
- regulating the foam pressure at the outlet of the foaming chamber for maintaining the foam mixing pressure in the foaming chamber at a determined value;
- providing the possibility to selectively adjust said determined value;
- the self-operating valve is preferably a pinch valve connected to the outlet of the foaming chamber for the step of regulating the foam pressure;
- the self-operating valve is adapted to regulate the foam pressure at the outlet of the foaming chamber with respect to a target air pressure applied to the self-operating valve;
- using a pressure regulator and a volume flow rate regulator for continuously supplying the mixture of foam agent and liquid to the foaming chamber at a first constant pressure and at a first constant volume flow rate;
- using a pressure regulator and a volume flow rate regulator for continuously supplying the compressed gas to the foaming chamber at a second constant pressure and at a second constant volume flow rate;
- setting the first volume flow rate for causing the superficial velocity of the mixture of foam agent and liquid in the foaming chamber to be at least 0.3 m/s, and more preferably at least 2 m/s;
- setting the first volume flow rate for causing the flow speed of the mixture of foam agent and liquid in the mixing chamber to be not more than 3 m/s;
- setting the second volume flow rate for causing the superficial velocity of the compressed-gas in the mixing chamber to be at least 0.3 m/s, and more preferably at least 2 m/s;
- setting the second volume flow rate for causing the superficial velocity of the compressed-gas in the mixing chamber to be not more than 3 m/s;
- setting the first and the second volume flow rates for providing in the mixing chamber a relative gas speed ratio greater than 0.3, more preferably greater than or equal to 0.4, and still more preferably greater than or equal to 0.5, but not more than 0.95, more preferably not more than 0.8 and more advantageously not more than 0.75;
- connecting one end of a pipe to the outlet of the foaming chamber, the other end of the pipe being connected to a foam-ejecting device, wherein the hydraulic cross section of the pipe is at least equal or greater than the hydraulic cross section of the foaming chamber.
According to another aspect, the invention proposes a compressed gas foam system, in particular a compressed air foam system, comprising:
- a foaming chamber having:
= a first inlet port for supplying compressed gas, preferably air, to the foaming chamber, = a second inlet port for supplying a mixture of liquid, preferably water, and at least one foam agent to the foaming chamber, and = an outlet port for outputting foam; and - a pressure-regulating arrangement connected to the outlet port for maintaining constant the foam pressure at the outlet of the foaming chamber characterized in that the pressure-regulating arrangement comprises a self-operating valve.
Preferred embodiments of the system comprise one or more of the following features:
- a pressure regulator for continuously supplying the mixture of foam agent and liquid to the foaming chamber at a first constant pressure;
- a volume flow rate regulator for continuously supplying the mixture of foam agent and liquid to the foaming chamber at a first constant volume flow rate;
- a pressure regulator for continuously supplying the compressed gas to the foaming chamber at a second constant pressure;
- a volume flow rate regulator for continuously supplying the compressed gas to the foaming chamber a second constant volume flow rate;
. CA 02685105 2014-08-06 - the self-operated valve, preferably comprises a pinch valve;
- a pipe connected to the outlet of the foaming chamber, the other end of the pipe being connected to a foam-ejecting device, wherein the hydraulic cross section of the pipe is at least equal or greater than the hydraulic cross section of the foaming chamber;
- the system is designed to implement the method according to the invention.
Within the invention as previously defined, the mentioned compressed gas can consist in a single gas, but can also be a mixture of several different gases as is the case for air. Similarly, within the invention, the mentioned liquid can consist in a single liquid, but can also be a mixture of several different liquids.
Further features and advantages of the invention will appear from the following description of embodiments of the invention, given as non-limiting examples, with reference to the accompanying drawings listed hereunder.
BRIEF DESCRIPTION OF THE DRAWING
Fig. 1 shows schematically a CAFS according to an embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
According to the invention, CAF is continuously produced by supplying both water containing at least a foaming agent and compressed air to a foaming chamber having an outlet for outputting. The mixture of foam agent and water is continuously supplied to the foaming chamber at a first constant pressure and at a first constant volume flow rate.
Similarly, the compressed air is continuously supplied to the foaming chamber at a second constant pressure and at a second constant volume flow rate. Further, the pressure in the foaming chamber ¨ that we will call hereafter foam mixing pressure - is regulated for maintaining said foam pressure constant, regardless of the possible lower pressure in the foam transporting line(s) connected at the outlet of the foaming chamber. The mentioned continuous production of foam and the continuous supply of compressed air and of the mixture of foam agent and water relates to the case in which the CAFS in use, i.e. in particular when the foam-ejecting device such as a nozzle arranged at the end of a pipe . CA 02685105 2014-08-06 connected to the outlet of the foaming chamber, is open. One will understand that the mentioned pressure regulation for maintaining the foam mixing pressure constant in the foaming chamber does not necessarily involve that the pressure is the same at any location through the foaming chamber. Indeed, the different parts of the foaming chamber may cause some pressure loss and as a result the pressure may differ somewhat from one location to another in the foaming chamber. It should be understood instead that as a consequence of the mentioned pressure regulation, the pressure does not substantially vary over time when considering a given location in the foaming chamber.
As a consequence, compressed air and the mixture of foam agent and water flow through the mixing chamber with each having a constant volume flow rate and a constant flow speed, independently notably of subsequent variation of pressure that may occur in the pipe(s) for transporting the foam from the foaming chamber to foam-ejecting devices. As a result, foam is continuously output by the foaming chamber with a constant quality. Further, there is no need for balancing the pressure and the volume flow rate of the compressed air and the mixture of foam agent and water.
Fig. 1 shows a CAFS according to a preferred embodiment of the invention. The CAFS
comprises a foaming chamber 5 supplied continuously with a mixture of water and at least one foam agent via a pressure regulator 2 and a volume flow rate regulator 4.
The foaming agent may be of any type suitable for fire fighting. Foaming chamber 5 is also supplied continuously with compressed air via a pressure regulator 1 and a volume flow rate regulator 3. Pressure regulators 1, 2 and volume flow rate regulators 3, 4 are provided with a view of supplying foaming chamber 5 with constant pressure and volume flow rates of air and of the mixture of foam agent and water, despite possible changes in the air source and/or in the water source. Foaming chamber 5 mixes the inputted compressed air and the mixture of foam agent and water to produce foam. Foaming chamber 5 may be of any known type.
Preferably, foaming chamber 5 is a static mixing chamber.
Water may be supplied from any suitable water source (not represented) such as a fire pump, a hydrant or a fixed water supply network in a building or a tunnel. Compressed air may classically be supplied by a compressor. Foaming agent is added continuously and homogeneously to water in an appropriate quantity by any appropriate technique such as described for instance in WO 2006/000177. The quantity of foaming agent added to the water is usually less than 1% of the total volume of the mixture of water and foam agent.
The outlet of foaming chamber 5 is connected to a pipe 8 for transporting the foam. A
foam-ejecting device 9 such as a nozzle is connected at the end of pipe 8.
Pipe 8 may be rigid or flexible according to the intended use. A pressure-regulating arrangement 6, 7 is arranged in pipe 8 at the outlet of foaming chamber 5. Pressure-regulating arrangement 6, 7 is adapted to maintain a constant pressure at the outlet of foaming chamber 5 and as a result it maintains also the foam mixing pressure in foaming chamber 5 constant. Thus, the foam mixing pressure in foaming chamber 5 does not vary due to the subsequent condition of pipe 8 and foam-ejecting device 9.
The foam pressure in foaming chamber 5 is maintained at a pressure that is set lower to the pressure of the mixture of foam agent and water and of the compressed air at the outlets of pressure regulators 1 and 2.
Maintaining the foam mixing pressure constant in foaming chamber 5 makes it possible to produce continuously foam with precisely controlled working parameters in the foaming chamber and that are stable over time. As a result, foam can be continuously produced with a constant quality. It has been found that this result is achieved due to the fact that the volume flow rates of air and of the mixture of foam agent and water that are determined by volume flow rate regulators 3, 4 set to given values are actually influenced by the difference of pressure between the inlet and the outlet of the volume flow rate regulators 3, 4. The fact of maintaining the foam mixing pressure constant in foaming chamber 5 in combination with pressure regulators 1, 2 causes the differences of pressure at the volume flow rate regulators 3, 4 to remain constant. As a consequence, the actual flow rates of air and of the mixture of foam agent and water supplied to foaming chamber 5 are constant too.
Pressure regulators 1, 2 may be pressure-limiting valves, notably of the type available on the market. Volume flow rate regulators 3, 4 may be volume flow rate regulating valves, notably of the type available on the market.
Further, pressure-regulating arrangement 6, 7 preferably comprises a self-operating valve 6, notably such as available on the market. In this case, the degree of aperture of the flow path through valve 6 is determined by the back pressure of the foam in pipe 8 and foam-ejecting device 9 in conjunction with the target pressure of valve 6.
As a result, there is no need of pressure sensors and controlling means such as a PLC
or an electronic circuit with a microcontroller for achieving a constant foam pressure. In other words, a self-operating valve provides for a very simple and cheap implementation.
Self-operating valve 6 is preferably adjustable. In other words, it is possible to selectively set self-operating valve 6 to a certain target pressure according to the wished water-air ratio. And as a consequence, self-operating valve 6 regulates the foam mixing pressure in foaming chamber 5 so as to equal the target pressure. As a consequence, it is possible to change the foam mixing pressure in foaming chamber 5 and thereby adjust the flow speed.
In a preferred embodiment shown in Fig. 1, the target pressure is provided pneumatically to self-operating valve 6. The target pressure may be provided via a pressure control valve 7 connected to the compressed air source used for supplying foaming chamber
5. Alternatively, the target pressure may applied to self-operating valve 6 hydraulically, electro-hydraulically, electro-pneumatically. Self-operating valve 6 may also be designed for setting the target pressure mechanically.
It is advantageous that self-operating valve 6 be a pinch valve (also called inner tube valve). Pinch valves are known in the art. Typically, a pinch valve is a straight through valve on which the valve element consists of a flexible sleeve which is distorted to control the flow of the fluid. In operation, the pinch valve does not adversely affect the bubbles in the foam produced by foaming chamber 5 even when the degree of aperture of the valve varies e.g. as a consequence of varying conditions in pipe 8 and foam ejecting-device 9.
Indeed, the pinch valve provides for a smooth ¨ i.e. flexible - variation of the cross section through the valve.
Further, the fluid path in the pinch valve is defined by smooth surfaces. As a result, the bubbles can smoothly pass through the valve without being adversely affected or destroyed as it may occur for valves having sharp edges in the flow path.
Pressure regulators 1, 2 and volume flow rate regulators 3, 4 may be respectively omitted in the case the air source and/or water source provide each the corresponding flow with the required pressure and volume flow rate.
For providing a foam of good quality and made homogeneously of tiny bubbles e.g.
with an average equivalent diameter in the range of 0.5 to 1 mm, the speed of the mixture of 10 foam agent and water flow in foaming chamber 5 is preferably at least 0.3 m/s, but more preferably at least 2 m/s. However, it is preferable that the speed thereof is not more than 3 m/s. Similarly, the speed of the compressed-air flow in foaming chamber 5 is preferably at least 0.3 m/s, but more preferably at least 2 m/s. However, it is preferable that the speed thereof is not more than 3 m/s either.
The mentioned speeds are not to be understood as actual speeds, but correspond to so-called superficial velocities that are calculated as follows:
Vair = VFRair / S (1) Vwater = VFRwater / S (2) wherein Vair: speed of the compressed air flow in foaming chamber 5, also called superficial velocity of the air in foaming chamber 5;
VFRair: volume flow rate of the compressed air at the inlet of foaming chamber 5;
Vwater: speed of the mixture of foam agent and water in foaming chamber 5, also called superficial velocity of this mixture in foaming chamber 5;
VFRwater: volume flow rate of the mixture of foam agent and water at the inlet of foaming chamber 5 S: hydraulic cross section of mixing chamber 5.
One will understand that these superficial velocities are calculated for one input flow as if the other input flow was not supplied to foaming chamber 5.
It is also preferable that the relative air speed ratio at the inlet of foaming chamber 5 is greater than 0.3, more preferably greater than or equal to 0.4. However, the relative air speed ratio is preferably not more than 0.95, more preferably not more than 0.8 and further more preferably not more than 0.75. The most preferred value of the relative air speed ratio is 0.5.
This relative air speed ratio 'R' is the ratio between the superficial velocity of the compressed-air and the sum of the superficial velocity of the compressed-air speed and the superficial velocity of the mixture of foam agent and water, these superficial velocities being those calculated above with formulae (1) and (2), i.e. R is calculated as follows:
R = Vair (Vair +
ater) (3) wherein Vair and Vwater are respectively those obtained with formulae (1) and (2) mentioned above.
Although not wanting to be bind by any theory, an explanation therefore might be that if the relative air speed ratio has a value beyond these limits, slip effects between the compressed air and the mixture of foam agent and water occur at such an extent that they do not mix correctly in foaming chamber 5 which as a result does produce foam of poor quality or even does not produce any foam.
The mentioned conditions can be met by defining adequately the hydraulic cross section of foaming chamber 5 in combination with the volume flow rates of the compressed air and of the mixture of foam agent and water at the inlet of foaming chamber 5 which are set by means of volume flow rate regulators 3, 4 under given settings of pressure regulators 1, 2 and pressure-regulating arrangement 6, 7.
For a same hydraulic cross section of foaming chamber 5 and for a same volume flow rate of compressed air supplied at the inlet of foaming chamber 5, it is possible to produce foam different from the preferred value of the relative air-speed ratio without the air speed and the speed of the mixture of foam agent and water getting out of the defined limits, by = CA 02685105 2014-08-06 , reducing the volume water flow rate supplied to foaming chamber 5.
Nevertheless, it is preferable not to diminish volume water flow rate so as to reach a superficial velocity of the mixture of water and foaming agent in foaming chamber 5 below 0.3 m/s as already mentioned. As a consequence, the produced foam is more or less wet or dry according to the setting. A suitable ratio of the volume flow rate of the mixture of foam agent and water (considered at 10 C) with respect to the volume flow rate of air considered at atmospheric pressure (considered at 0 C) ¨ called hereafter water air ratio - for extinguishing fire is 1:7.
But this ratio can be changed, preferably within the range from 1:5 up to 1:21 notably by means of the mentioned change in settings. The CAFS may be designed to provide the user the possibility to change this ratio selectively with a control device, the CAFS
changing accordingly the foam pressure and the flow rate of the mixture of foam agent and water flow by changing the setting of volume flow rate regulator 4 and pressure-regulating arrangement 6, 7.
One will understand that the foam pressure at the outlet of foaming chamber 5 is greater than the foam pressure at the inlet of foam-ejecting device 9. That difference of pressure allows the foam to be transported through pipe 8. This difference of pressure causes an expansion of the foam in pipe 8. It has been found that when the foam speed gets too high, the bubbles of the foam get destroyed due to external and internal friction as well as shearing forces. To prevent this detrimental effect, it has been found that an optimal cross section of pipe 8 can be selected in consideration of the volume flow rate and the pressure at the end of pipe 8 (at foam-ejecting device 9). In particular, it has been found that it is preferable to choose the cross section of pipe 8 at least equal or larger than the hydraulic cross section of foaming chamber 5.
It is advantageous that self-operating valve 6 be a pinch valve (also called inner tube valve). Pinch valves are known in the art. Typically, a pinch valve is a straight through valve on which the valve element consists of a flexible sleeve which is distorted to control the flow of the fluid. In operation, the pinch valve does not adversely affect the bubbles in the foam produced by foaming chamber 5 even when the degree of aperture of the valve varies e.g. as a consequence of varying conditions in pipe 8 and foam ejecting-device 9.
Indeed, the pinch valve provides for a smooth ¨ i.e. flexible - variation of the cross section through the valve.
Further, the fluid path in the pinch valve is defined by smooth surfaces. As a result, the bubbles can smoothly pass through the valve without being adversely affected or destroyed as it may occur for valves having sharp edges in the flow path.
Pressure regulators 1, 2 and volume flow rate regulators 3, 4 may be respectively omitted in the case the air source and/or water source provide each the corresponding flow with the required pressure and volume flow rate.
For providing a foam of good quality and made homogeneously of tiny bubbles e.g.
with an average equivalent diameter in the range of 0.5 to 1 mm, the speed of the mixture of 10 foam agent and water flow in foaming chamber 5 is preferably at least 0.3 m/s, but more preferably at least 2 m/s. However, it is preferable that the speed thereof is not more than 3 m/s. Similarly, the speed of the compressed-air flow in foaming chamber 5 is preferably at least 0.3 m/s, but more preferably at least 2 m/s. However, it is preferable that the speed thereof is not more than 3 m/s either.
The mentioned speeds are not to be understood as actual speeds, but correspond to so-called superficial velocities that are calculated as follows:
Vair = VFRair / S (1) Vwater = VFRwater / S (2) wherein Vair: speed of the compressed air flow in foaming chamber 5, also called superficial velocity of the air in foaming chamber 5;
VFRair: volume flow rate of the compressed air at the inlet of foaming chamber 5;
Vwater: speed of the mixture of foam agent and water in foaming chamber 5, also called superficial velocity of this mixture in foaming chamber 5;
VFRwater: volume flow rate of the mixture of foam agent and water at the inlet of foaming chamber 5 S: hydraulic cross section of mixing chamber 5.
One will understand that these superficial velocities are calculated for one input flow as if the other input flow was not supplied to foaming chamber 5.
It is also preferable that the relative air speed ratio at the inlet of foaming chamber 5 is greater than 0.3, more preferably greater than or equal to 0.4. However, the relative air speed ratio is preferably not more than 0.95, more preferably not more than 0.8 and further more preferably not more than 0.75. The most preferred value of the relative air speed ratio is 0.5.
This relative air speed ratio 'R' is the ratio between the superficial velocity of the compressed-air and the sum of the superficial velocity of the compressed-air speed and the superficial velocity of the mixture of foam agent and water, these superficial velocities being those calculated above with formulae (1) and (2), i.e. R is calculated as follows:
R = Vair (Vair +
ater) (3) wherein Vair and Vwater are respectively those obtained with formulae (1) and (2) mentioned above.
Although not wanting to be bind by any theory, an explanation therefore might be that if the relative air speed ratio has a value beyond these limits, slip effects between the compressed air and the mixture of foam agent and water occur at such an extent that they do not mix correctly in foaming chamber 5 which as a result does produce foam of poor quality or even does not produce any foam.
The mentioned conditions can be met by defining adequately the hydraulic cross section of foaming chamber 5 in combination with the volume flow rates of the compressed air and of the mixture of foam agent and water at the inlet of foaming chamber 5 which are set by means of volume flow rate regulators 3, 4 under given settings of pressure regulators 1, 2 and pressure-regulating arrangement 6, 7.
For a same hydraulic cross section of foaming chamber 5 and for a same volume flow rate of compressed air supplied at the inlet of foaming chamber 5, it is possible to produce foam different from the preferred value of the relative air-speed ratio without the air speed and the speed of the mixture of foam agent and water getting out of the defined limits, by = CA 02685105 2014-08-06 , reducing the volume water flow rate supplied to foaming chamber 5.
Nevertheless, it is preferable not to diminish volume water flow rate so as to reach a superficial velocity of the mixture of water and foaming agent in foaming chamber 5 below 0.3 m/s as already mentioned. As a consequence, the produced foam is more or less wet or dry according to the setting. A suitable ratio of the volume flow rate of the mixture of foam agent and water (considered at 10 C) with respect to the volume flow rate of air considered at atmospheric pressure (considered at 0 C) ¨ called hereafter water air ratio - for extinguishing fire is 1:7.
But this ratio can be changed, preferably within the range from 1:5 up to 1:21 notably by means of the mentioned change in settings. The CAFS may be designed to provide the user the possibility to change this ratio selectively with a control device, the CAFS
changing accordingly the foam pressure and the flow rate of the mixture of foam agent and water flow by changing the setting of volume flow rate regulator 4 and pressure-regulating arrangement 6, 7.
One will understand that the foam pressure at the outlet of foaming chamber 5 is greater than the foam pressure at the inlet of foam-ejecting device 9. That difference of pressure allows the foam to be transported through pipe 8. This difference of pressure causes an expansion of the foam in pipe 8. It has been found that when the foam speed gets too high, the bubbles of the foam get destroyed due to external and internal friction as well as shearing forces. To prevent this detrimental effect, it has been found that an optimal cross section of pipe 8 can be selected in consideration of the volume flow rate and the pressure at the end of pipe 8 (at foam-ejecting device 9). In particular, it has been found that it is preferable to choose the cross section of pipe 8 at least equal or larger than the hydraulic cross section of foaming chamber 5.
Claims (19)
1. Method for continuously producing compressed-gas foam, preferably compressed-air foam, notably for fire fighting or for decontamining, by supplying both compressed gas, preferably compressed air, and a mixture of liquid, preferably water, and at least a foam agent to a foaming chamber (5) having an outlet for outputting foam, comprising the steps of:
- continuously supplying the mixture of foam agent and liquid to the foaming chamber at a first constant pressure and at a first constant volume flow rate;
- continuously supplying the compressed gas to the foaming chamber at a second constant pressure and at a second constant volume flow rate;
- regulating the foam pressure at the outlet of the foaming chamber for maintaining the foam mixing pressure in the foaming chamber constant by using a self-operating valve connected to the outlet of the foaming chamber.
- continuously supplying the mixture of foam agent and liquid to the foaming chamber at a first constant pressure and at a first constant volume flow rate;
- continuously supplying the compressed gas to the foaming chamber at a second constant pressure and at a second constant volume flow rate;
- regulating the foam pressure at the outlet of the foaming chamber for maintaining the foam mixing pressure in the foaming chamber constant by using a self-operating valve connected to the outlet of the foaming chamber.
2. Method according to claim 1, further comprising:
- regulating the foam pressure at the outlet of the foaming chamber for maintaining the foam mixing pressure in the foaming chamber at a determined value.
- regulating the foam pressure at the outlet of the foaming chamber for maintaining the foam mixing pressure in the foaming chamber at a determined value.
3. Method according to claim 2, further comprising:
- providing the possibility to selectively adjust said determined value.
- providing the possibility to selectively adjust said determined value.
4. Method according to any one of claims 1 to 3, wherein the self-operating valve is a pinch valve.
5. Method according to any one of claims 1 to 4, wherein the self-operating valve is adapted to regulate the foam pressure at the outlet of the foaming chamber with respect to a target gas pressure applied to the self-operating valve.
6. Method according to any one of claims 1 to 5, using a pressure regulator (2) and a volume flow rate regulator (4) for continuously supplying the mixture of foam agent and liquid to the foaming chamber at a first constant pressure and at a first constant volume flow rate.
7. Method according to any one of claims 1 to 6, using a pressure regulator (1) and a volume flow rate regulator (3) for continuously supplying the compressed gas to the foaming chamber at a second constant pressure and at a second constant volume flow rate.
8. Method according to any one of claims 1 to 7, comprising the step of:
- setting the first volume flow rate for causing the superficial velocity of the mixture of foam agent and liquid in the foaming chamber to be at least 0.3 m/s, and more preferably at least 2 m/s.
- setting the first volume flow rate for causing the superficial velocity of the mixture of foam agent and liquid in the foaming chamber to be at least 0.3 m/s, and more preferably at least 2 m/s.
9. Method according to any one of claims 1 to 8, comprising the step of:
- setting the first volume flow rate for causing the superficial velocity of the mixture of foam agent and liquid in the mixing chamber to be not more than 3 m/s.
- setting the first volume flow rate for causing the superficial velocity of the mixture of foam agent and liquid in the mixing chamber to be not more than 3 m/s.
10. Method according to any one of claims 1 to 9, comprising the step of:
- setting the second volume flow rate for causing the superficial velocity of the compressed-gas in the mixing chamber to be at least 0.3 m/s, and more preferably at least 2 rn/s.
- setting the second volume flow rate for causing the superficial velocity of the compressed-gas in the mixing chamber to be at least 0.3 m/s, and more preferably at least 2 rn/s.
11. Method according to any one of claims 1 to 10, comprising the step of:
- setting the second volume flow rate for causing the superficial velocity of the compressed-gas in the mixing chamber to be not more than 3 m/s.
- setting the second volume flow rate for causing the superficial velocity of the compressed-gas in the mixing chamber to be not more than 3 m/s.
12. Method according to any one of claims 1 to 11, comprising the step of:
- setting the first and the second volume flow rates for providing in the mixing chamber a relative gas speed ratio greater than 0.3, more preferably greater than or equal to 0.4, still more preferably greater than or equal to 0.5, but not more than 0.95, more preferably not more than 0.8 and more advantageously not more than 0.75, wherein the relative gas speed ratio, noted R, is calculated with the following formula:
R = V gas / (V gas + V liquid) wherein V gas and V liquid are calculated with the following formula:
V gas = VFR gas / S (1) V liquid VFR liquid S
wherein : VFR gas is the second constant volume flow rate, VFR liquid is the first constant volume flow rate, S is the hydraulic cross section of the foaming chamber.
- setting the first and the second volume flow rates for providing in the mixing chamber a relative gas speed ratio greater than 0.3, more preferably greater than or equal to 0.4, still more preferably greater than or equal to 0.5, but not more than 0.95, more preferably not more than 0.8 and more advantageously not more than 0.75, wherein the relative gas speed ratio, noted R, is calculated with the following formula:
R = V gas / (V gas + V liquid) wherein V gas and V liquid are calculated with the following formula:
V gas = VFR gas / S (1) V liquid VFR liquid S
wherein : VFR gas is the second constant volume flow rate, VFR liquid is the first constant volume flow rate, S is the hydraulic cross section of the foaming chamber.
13. Method according to any one of claims 1 to 12, comprising the step of:
- connecting one end of a pipe (8) to the outlet of the foaming chamber, the other end of the pipe being connected to a foam-ejecting device (9), wherein the hydraulic cross section of the pipe is at least equal or greater than the hydraulic cross section of the foaming chamber.
- connecting one end of a pipe (8) to the outlet of the foaming chamber, the other end of the pipe being connected to a foam-ejecting device (9), wherein the hydraulic cross section of the pipe is at least equal or greater than the hydraulic cross section of the foaming chamber.
14. A compressed gas foam system, preferably a compressed air foam system, comprising:
- a foaming chamber (5) having:
.cndot. a first inlet port (11) for supplying compressed gas, preferably compressed air, to the foaming chamber, .cndot. a second inlet port (10) for supplying a mixture of liquid, preferably water, and at least one foam agent to the foaming chamber, and .cndot. an outlet port (12) for outputting foam; and - a pressure-regulating arrangement (6, 7) connected to the outlet port (12) for maintaining constant the foam pressure at the outlet of the foaming chamber, characterized in that the pressure-regulating arrangement comprises a self-operating valve (6).
- a foaming chamber (5) having:
.cndot. a first inlet port (11) for supplying compressed gas, preferably compressed air, to the foaming chamber, .cndot. a second inlet port (10) for supplying a mixture of liquid, preferably water, and at least one foam agent to the foaming chamber, and .cndot. an outlet port (12) for outputting foam; and - a pressure-regulating arrangement (6, 7) connected to the outlet port (12) for maintaining constant the foam pressure at the outlet of the foaming chamber, characterized in that the pressure-regulating arrangement comprises a self-operating valve (6).
15. The system according to claim 14, further comprising a pressure regulator (2) and a volume flow rate regulator (4) for continuously supplying the mixture of foam agent and liquid to the foaming chamber at a first constant pressure and at a first constant volume flow rate.
16. The system according to claim 14 or 15, further comprising a pressure regulator (1) and a volume flow rate regulator (3) for continuously supplying the compressed gas to the foaming chamber at a second constant pressure and at a second constant volume flow rate.
17. The system according to any one of claims 14 to 16, wherein the self-operating valve (6) is a pinch valve.
18. The system according to any one of claims 14 to 17, further comprising a pipe (8) connected to the outlet of the foaming chamber, the other end of the pipe being connected to a foam-ejecting device (9), wherein the hydraulic cross section of the pipe is at least equal or greater than the hydraulic cross section of the foaming chamber.
19. The system according to any one of claims 14 to 18, designed to implement the method according to any one of claims 1 to 13.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP07008599.8 | 2007-04-27 | ||
| EP07008599A EP1985333A1 (en) | 2007-04-27 | 2007-04-27 | Improved compressed air foam technology |
| PCT/IB2008/001355 WO2008132604A1 (en) | 2007-04-27 | 2008-04-24 | Improved compressed air foam technology |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2685105A1 CA2685105A1 (en) | 2008-11-06 |
| CA2685105C true CA2685105C (en) | 2015-09-01 |
Family
ID=38222204
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA2685105A Expired - Fee Related CA2685105C (en) | 2007-04-27 | 2008-04-24 | Improved compressed air foam technology |
Country Status (10)
| Country | Link |
|---|---|
| US (1) | US8573317B2 (en) |
| EP (2) | EP1985333A1 (en) |
| JP (1) | JP5244903B2 (en) |
| CN (1) | CN101754785B (en) |
| BR (1) | BRPI0811417A2 (en) |
| CA (1) | CA2685105C (en) |
| ES (1) | ES2395204T3 (en) |
| PT (1) | PT2144676E (en) |
| RU (1) | RU2456037C2 (en) |
| WO (1) | WO2008132604A1 (en) |
Families Citing this family (27)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2460643C1 (en) * | 2008-06-30 | 2012-09-10 | Серебель-Инвест Са | Method of casting poly-1,4-dioxanone |
| CN104080699B (en) | 2012-01-27 | 2016-12-14 | 森普莱克斯制造有限公司 | Air attack system |
| DE102012004680A1 (en) * | 2012-03-12 | 2013-09-12 | Rwe Power Ag | Apparatus and method for providing a foam |
| CN103111033B (en) * | 2013-02-26 | 2015-10-21 | 王靖 | A kind of Liqiud-gas mixing device |
| US11643946B2 (en) | 2013-10-02 | 2023-05-09 | Aerocore Technologies Llc | Cleaning method for jet engine |
| CA2963071C (en) | 2013-10-02 | 2022-09-27 | Aerocore Technologies Llc | Cleaning method for jet engine |
| US20150283523A1 (en) * | 2014-04-03 | 2015-10-08 | Waterous Company | Compressed air foam generation |
| US20160186602A1 (en) * | 2014-12-31 | 2016-06-30 | Aerocore Technologies Llc | Nozzle for foam washing of jet engine |
| CN104958847B (en) * | 2015-06-09 | 2018-05-15 | 公安部天津消防研究所 | Compressed air foam fire-extinguishing apparatus for large-scale floating roof tank |
| WO2017013472A1 (en) * | 2015-07-23 | 2017-01-26 | One Seven Middle East Safety Equipments Llc. | Device and method for producing compressed air foam for fighting fires, and fire-fighting device |
| RU2622815C1 (en) * | 2016-04-14 | 2017-06-20 | ФЕДЕРАЛЬНОЕ ГОСУДАРСТВЕННОЕ БЮДЖЕТНОЕ УЧРЕЖДЕНИЕ "ВСЕРОССИЙСКИЙ ОРДЕНА "ЗНАК ПОЧЕТА" НАУЧНО-ИССЛЕДОВАТЕЛЬСКИЙ ИНСТИТУТ ПРОТИВОПОЖАРНОЙ ОБОРОНЫ МИНИСТЕРСТВА РОССИЙСКОЙ ФЕДЕРАЦИИ ПО ДЕЛАМ ГРАЖДАНСКОЙ ОБОРОНЫ, ЧРЕЗВЫЧАЙНЫМ СИТУАЦИЯМ И ЛИКВИДАЦИИ ПОСЛЕДСТВИЙ СТИХИЙНЫХ БЕДСТВИЙ" (ФГБУ ВНИИПО МЧС России) | Device for self-spumescent gas filled foam production |
| US10406390B2 (en) | 2016-08-09 | 2019-09-10 | Simplex Manufacturing Co. | Aerial fire suppression system |
| CN106729829A (en) * | 2017-01-11 | 2017-05-31 | 重庆军通汽车有限责任公司 | A kind of washing and disinfection car emulsification modulating device and its emulsification modulator approach |
| RU178495U1 (en) * | 2017-03-10 | 2018-04-05 | Федеральное Государственное Бюджетное Образовательное Учреждение Высшего Образования (ФГБОУ ВО) "Уральский Государственный Аграрный Университет" (УрГАУ) (отдел по научной, инновационной работе и докторантуре) | BUILT-IN FOAM RECEIVER |
| CN107587892B (en) * | 2017-10-23 | 2023-11-17 | 山西潞安环保能源开发股份有限公司常村煤矿 | A fine atomization foam dust collector for suppressing dust under mine |
| RU2678257C1 (en) * | 2018-04-13 | 2019-01-24 | ФЕДЕРАЛЬНОЕ ГОСУДАРСТВЕННОЕ БЮДЖЕТНОЕ УЧРЕЖДЕНИЕ "ВСЕРОССИЙСКИЙ ОРДЕНА "ЗНАК ПОЧЕТА" НАУЧНО-ИССЛЕДОВАТЕЛЬСКИЙ ИНСТИТУТ ПРОТИВОПОЖАРНОЙ ОБОРОНЫ МИНИСТЕРСТВА РОССИЙСКОЙ ФЕДЕРАЦИИ ПО ДЕЛАМ ГРАЖДАНСКОЙ ОБОРОНЫ, ЧРЕЗВЫЧАЙНЫМ СИТУАЦИЯМ И ЛИКВИДАЦИИ ПОСЛЕДСТВИЙ СТИХИЙНЫХ БЕДСТВИЙ" (ФГБУ ВНИИПО МЧС России) | Method of obtaining self-foaming gas-filled foam and device for its implementation |
| CN109046056B (en) * | 2018-08-23 | 2024-02-27 | 芜湖美的厨卫电器制造有限公司 | Microbubble device and water heater |
| CN111720390B (en) * | 2019-10-08 | 2021-08-17 | 中国科学院上海微***与信息技术研究所 | Fluid flow velocity stabilizing system |
| IT201900023679A1 (en) * | 2019-12-11 | 2021-06-11 | Iveco Magirus | CAFS SYSTEM EQUIPPED WITH AN IMPROVED AIR MANAGEMENT SYSTEM |
| CN110975193B (en) * | 2019-12-24 | 2024-05-28 | 磐龙安全技术有限公司 | Compressed air foam fluid mixing device |
| CN113134200B (en) * | 2020-01-20 | 2022-05-17 | 南京南瑞继保电气有限公司 | Net type fine diffuser special for air foam fire extinguishing equipment |
| DE102020209211A1 (en) * | 2020-07-22 | 2022-01-27 | Albert Ziegler Gmbh | Process for providing a liquid working foam composition and foam preparation apparatus |
| CN112156403B (en) * | 2020-10-14 | 2021-08-13 | 应急管理部天津消防研究所 | Compressed air foam gas-liquid mixer and design method |
| CN112972946A (en) * | 2021-03-04 | 2021-06-18 | 湖北江南专用特种汽车有限公司 | Compressed air foam generating device and control method thereof |
| CN113359416B (en) * | 2021-06-11 | 2023-04-25 | 西安理工大学 | PLC-based multi-input single-output compressed air foam system and control method |
| CN114949699B (en) * | 2021-10-21 | 2023-01-31 | 新余博迅汽车有限公司 | Vehicle-mounted fire-fighting system and method and fire-fighting vehicle |
| CN115350426B (en) * | 2022-08-31 | 2023-07-07 | 徐工消防安全装备有限公司 | Fire-fighting foam foaming device, fire-fighting foam foaming system and foaming method |
Family Cites Families (22)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB314438A (en) * | 1928-06-27 | 1930-04-03 | Wilhelm Friedrich | Improvements in and relating to foam-producing apparatus |
| DE2233176A1 (en) * | 1972-07-06 | 1974-01-31 | Preussag Ag Minimax | METHOD AND DEVICE FOR GENERATING AIR FOAM FOR FIRE EXTINGUISHING PURPOSES |
| JPS5424493A (en) | 1977-07-26 | 1979-02-23 | Onoda Cement Co Ltd | Foam fire extinguisher |
| DE3034622A1 (en) * | 1980-09-13 | 1982-04-01 | Rheinische Braunkohlenwerke AG, 5000 Köln | Foam generating and conveying equipment - uses foam agent-water mixture with introduction of compressed air |
| US4584002A (en) * | 1981-06-22 | 1986-04-22 | Halliburton Company | Recirculating foam generator |
| AU3258793A (en) * | 1992-01-17 | 1993-08-03 | Inter Airspray Sweden Ab | Foam-spraying device |
| CA2081392A1 (en) * | 1992-10-26 | 1994-04-27 | Toshiharu Fukai | Nozzle for generating bubbles |
| CN2155242Y (en) * | 1993-06-18 | 1994-02-09 | 中国石化北京设计院 | Foam fire-extinguishing device |
| US5632338A (en) * | 1995-08-31 | 1997-05-27 | The Hunter Group Corporation | Low pressure, self-contained fire suppression system |
| US5803596A (en) * | 1996-05-17 | 1998-09-08 | Stephens; Patrick J. | Method and apparatus for high capacity production of finished aqueous foam with continuously adjustable proportioning |
| US6109359A (en) * | 1999-03-23 | 2000-08-29 | Ballard; Paul Corwin | Compressed air foam system |
| RU2167060C2 (en) * | 1999-04-05 | 2001-05-20 | Сибирский государственный технологический университет | Portable unit for production of foamed self-hardening compounds |
| DE10010141C1 (en) | 2000-03-03 | 2001-10-04 | Ulrich Braun | Mixing chamber for producing compressed air foam for fire extinguishing devices has internal contour narrowing preferably conical towards compressed air foam outlet for better foam production |
| CN2468514Y (en) | 2001-04-11 | 2002-01-02 | 中国科学技术大学 | Portable and pulsation type jetting fire extinguishing gun |
| US6991041B2 (en) * | 2003-02-28 | 2006-01-31 | Hale Products, Inc. | Compressed air foam pumping system |
| RU2257527C2 (en) * | 2003-03-24 | 2005-07-27 | Военно-инженерный Университет | Plant for generating and dispersal of special of special materials |
| JP2004360813A (en) | 2003-06-05 | 2004-12-24 | Seiko Instruments Inc | Autonomous valve |
| RU2254155C1 (en) * | 2004-03-10 | 2005-06-20 | Душкин Андрей Леонидович | Portable fire-extinguishing device and liquid atomizer |
| DE202004010339U1 (en) * | 2004-06-28 | 2004-10-21 | Schmitz Gmbh Feuerwehr- Und Umwelttechnik | Compressed air foam fire extinguishing system for a tunnel |
| DE102004032020B4 (en) * | 2004-06-28 | 2006-11-30 | Schmitz Gmbh Feuerwehr- Und Umwelttechnik | Process and arrangement for the production of compressed air foam for fire fighting and decontamination |
| JP4135790B2 (en) | 2004-12-20 | 2008-08-20 | 能美防災株式会社 | Foaming equipment mixing equipment |
| RU2297260C1 (en) * | 2005-10-04 | 2007-04-20 | Государственное образовательное учреждение высшего профессионального образования "Санкт-Петербургский государственный технологический институт (технический университет)" | Foam generation device |
-
2007
- 2007-04-27 EP EP07008599A patent/EP1985333A1/en not_active Withdrawn
-
2008
- 2008-04-24 RU RU2008151529/12A patent/RU2456037C2/en not_active IP Right Cessation
- 2008-04-24 US US12/596,853 patent/US8573317B2/en not_active Expired - Fee Related
- 2008-04-24 BR BRPI0811417-0A patent/BRPI0811417A2/en not_active Application Discontinuation
- 2008-04-24 EP EP08751055A patent/EP2144676B1/en not_active Not-in-force
- 2008-04-24 WO PCT/IB2008/001355 patent/WO2008132604A1/en active Application Filing
- 2008-04-24 ES ES08751055T patent/ES2395204T3/en active Active
- 2008-04-24 JP JP2010504903A patent/JP5244903B2/en not_active Expired - Fee Related
- 2008-04-24 CA CA2685105A patent/CA2685105C/en not_active Expired - Fee Related
- 2008-04-24 PT PT87510558T patent/PT2144676E/en unknown
- 2008-04-24 CN CN2008800130417A patent/CN101754785B/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN101754785A (en) | 2010-06-23 |
| US8573317B2 (en) | 2013-11-05 |
| PT2144676E (en) | 2012-12-11 |
| EP2144676B1 (en) | 2012-08-29 |
| JP5244903B2 (en) | 2013-07-24 |
| CN101754785B (en) | 2013-11-27 |
| WO2008132604A1 (en) | 2008-11-06 |
| EP2144676A1 (en) | 2010-01-20 |
| ES2395204T3 (en) | 2013-02-11 |
| CA2685105A1 (en) | 2008-11-06 |
| RU2008151529A (en) | 2010-06-27 |
| BRPI0811417A2 (en) | 2015-06-16 |
| JP2010525851A (en) | 2010-07-29 |
| EP1985333A1 (en) | 2008-10-29 |
| RU2456037C2 (en) | 2012-07-20 |
| US20100126738A1 (en) | 2010-05-27 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request |
Effective date: 20130312 |
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| MKLA | Lapsed |
Effective date: 20190424 |